1. Field of the Invention
This invention relates to a data carrier with an optically variable structure verifying the authenticity of the data carrier and including an embossed screen which is combined with a coating contrasting with the surface of the data carrier in such a way that at least partial areas of the coating are completely visible upon perpendicular viewing but concealed upon oblique viewing, so that a tilting effect arises upon alternate perpendicular and oblique viewing, i.e. first information is recognizable at least at one predetermined angle but invisible or barely visible upon perpendicular viewing.
2. Related Art
For protection against imitation, in particular with color copiers or other reproduction methods, one equips data carriers, for example bank notes, papers of value, credit or identity cards or the like, with optically variable security elements, in particular holograms. This protection from forgery is based on the fact that the optically variable effect, which is readily and clearly recognizable visually, cannot be rendered, or not rendered properly, by the abovementioned reproduction devices. A data carrier with such a hologram is known e.g. from EP 440 045 A2. This print proposes applying the hologram as a prefabricated element or as an embossing in a layer of lacquer applied to the data carrier.
However, other optically variable elements can also be incorporated in data carriers alongside these holograms. For example CA 1019 012 discloses a bank note which is provided with a parallel printed line pattern in a partial area of its surface. To produce the optically variable effect a line structure is additionally embossed into the data carrier in the area of this line pattern so as to create flanks which are visible only at certain viewing angles. By selectively disposing the line pattern on like-oriented flanks one can make the lines visible upon oblique viewing of the flanks provided with these lines, while the line pattern is not recognizable upon oblique viewing of the backs of the flanks. If one provides phase jumps in the line screen or in the embossed screen in partial areas of the embossed surface one can represent information which is recognizable either only from the first oblique viewing angle or only from the second viewing angle.